Ever since I saw the wonderful wildlife tower Nigel Dunnett built (with, no doubt, the aid of a small army of helpers) for his 2009 Chelsea show garden, Future Nature, I’ve had a bit of a thing for them. It’s not often, after all, that you come across something that’s useful in the garden, doesn’t cost a penny, yet – unlike most things with what might be called an allotment aesthetic – looks fabulous.

I came across this one at a spring open day held at the Magdalen Project, a sort of experimental eco-smallholding place just round the corner from where I live. It was tucked away at the back of a not particularly inspiring – mainly because it had only just been planted – forest garden. Though the jury is still out, for me, on forest gardens, I am totally sold on the whole idea of bug blocks, wildlife stacks, call them what you will.

It was made from old pallets, sawn in half and stacked: if you use full-width pallets you’ll only fill the outer six inches or so, therefore to save space you really only need the end bit (this also means you only need three pallets for a six-storey stack, if you get my drift, as you use the two halves on top of each other).

Then you just let your imagination rip to create as many little hidey-holes for bugs and beasties as you can. I loved the way they used roof tiles on the top stuffed with holey stones gathered from the beach.

Bits of old garden hose inside a flowerpot on its side….

…and these rather pretty old slates, interwoven with larger stones to create not only gaps for small things to crawl into (looks like this bit is a favourite with spiders) but also a range of textures and colour, part of what makes these things so pretty.

You can just about make out next door another flowerpot filled with hollow stems – the dried-out remains of cardoons, run-to-seed parsnips and carrots, or Queen Anne’s lace from the hedgerows are ideal.

Anything can be co-opted for use: here some old engineering bricks with bits of cane stuck into the holes. You could of course just leave the holes open: the canes just add a bit of quirkiness. The blocks which hold the pallets together have holes of varying sizes drilled into them, too.

And if you don’t like the whole pallets thing, there are other shapes and combinations you can use: here a tower of marine ply circles built up like a wedding cake on sturdy lengths of fencepost and topped with a bicycle tyre. Personally I prefer the ‘conventional’ pallet look: and whichever you choose, it’s a fantastic project to do with the kids on aimless school holiday weekdays.

There’s a very serious point to all this imagination and frippery: there are so many benefits of attracting insects to your garden. Pollinators – and pest-devouring creatures like beetles, frogs and toads – need every bit of help we can give them, thanks to our tendencies to throw pesticide cocktails around and remove every wildflower we can strip out of the countryside in favour of executive homes. By giving them somewhere safe to live, not only are you helping out your garden (especially if you grow veg), you’re doing your bit for biodiversity too.

I’ve already squirrelled away my first pallet (is there anything, I wonder, for which pallets are not useful?) and I can no longer pass a skip without having a quick peep inside just in case. I’ve even got the perfect spot for it: just below the window in what will, one day, be my fruit cage – a place where I need as many pollinators and pest-eaters as I can get. Time to get creative…